Measures of Outcome in Metastatic Breast Cancer: Insights From a Real-World Scenario

Abstract

No gold standard treatment exists for metastatic breast cancer (MBC). Clinical decision making is based on knowledge of prognostic and predictive factors that are extrapolated from clinical trials and, sometimes, are not reliably transferable to a real-world scenario. Moreover, misalignment between endpoints used in drug development and measures of outcome in clinical practice has been noted.The roles of overall survival (OS) and progression-free survival (PFS) as primary endpoints in the context of clinical trials are the subjects of lively debate. Information about these parameters in routine clinical practice is potentially useful to design new studies and/or to interpret the results of clinical research. This study analyzed the impact of patient and tumor characteristics on the major measures of outcome across different lines of treatment in a cohort of 472 patients treated for MBC. OS, PFS, and postprogression survival (PPS) were analyzed. The study showed how biological and clinical characteristics may have different prognostic value across different lines of therapy for MBC. After first-line treatment, the median PPS of luminal A, luminal B, and human epidermal growth factor receptor 2 (HER2)-positive groups was longer than 12 months. The choice of OS as a primary endpoint for clinical trials could not be appropriate with these subtypes. In contrast, OS could be an appropriate endpoint when PPS is expected to be low (e.g., triple-negative subtype after the first line; other subtypes after the third line). The potential implications of these findings are clinical and methodological. The Oncologist 2014;19:608-615 Implications for Practice: Although randomized clinical trials are recognized as the highest level of scientific evidence to demonstrate the efficacy of a treatment, sometimes they do not reflect the clinical circumstances faced in a real-world scenario. The present study provides data about outcomes of consecutive metastatic breast cancer patients treated at an academic hospital. The findings support the importance of considering breast cancer in distinct subgroups with the aim of obtaining more precise information about prognosis and expected benefit from treatment. The study also provides insights for future clinical trial design.

Advancement of mass spectrometry-based proteomics technologies to explore triple negative breast cancer

“…However, this comes at the expense of increased chemotherapeutic toxicity and has no impact on patient survival 84 . In fact, less than 30% of women with metastatic breast cancer will survive five years after initial diagnosis despite systematic chemotherapy and virtually all metastatic TNBC patients eventually die of this disease 85 . To overcome this TNBC paradox, there is an urgent need to further sub-classify this aggressive cancer subtype to help in the development of more targeted patient treatments with better clinical outcomes.…”

Patterns of distant metastasis in Chinese women according to breast cancer subtypes

“…Although great progress has been made in the comprehensive treatment of breast cancer, 20%-30% of patients will still develop distant metastases [3–5]. Bone, lung, liver, and brain are the most common metastatic sites of breast cancer [6], but there is a difference in the survival of patients for different metastatic sites [7, 8]. …”

Tumor neovasculature-targeted cationic PEGylated liposomes of gambogic acid for the treatment of triple-negative breast cancer

“…Moreover, unlike the other type of solid tumor, TNBC patients have susceptibility towards development of visceral metastases early in the course of the disease. Developments of effective approaches with improved treatment potential against these cancers are critical as the survival rate of patients with metastatic TNBC is very few months (Bonotto et al, 2014). Very poor prognosis and limited treatment options due to lack to typical breast cancer markers, are the two basic factors compromising the cure of TNBC today.…”